Statistical characteristics of formation and evolution of structure in the Universe

Abstract

ABSTRA C T An approximate statistical description of the formation and evolution of structure of the Universe based on the Zel’dovich theory of gravitational instability is proposed. It is found that the evolution of dark matter (DM) structure shows features of self-similarity and the main structure characteristics can be expressed through the parameters of the initial power spectrum and cosmological model. For the CDM-like power spectrum and suitable parameters of the cosmological model the effective matter compression reaches the observed scales Rwall , 20‐25h 21 Mpc with the typical mean separation of wall-like elements DSLSS , 50‐70h 21 Mpc. This description can be directly applied to the deep pencil beam galactic surveys and absorption spectra of quasars. For larger 3D catalogues and simulations it can be applied to results obtained with the core-sampling analysis. It is shown that the interaction of large- and small-scale perturbations modulates the creation rate of early Zel’dovich pancakes and generates bias on the SLSS scale. For suitable parameters of the cosmological model and reheating process this bias can essentially improve the characteristics of simulated structure of the Universe. The models with 0:3 # Vm # 0:5 give the best description of the observed structure parameters. The influence of low-mass ‘warm’ dark matter particles, such as a massive neutrino, will extend the acceptable range of Vm and h.